International Journal of Pharmaceutical and Life Sciences ISSN 2305-0330 Volume 2, Issue 1: January 2013 AGARWOOD PRODUCTION- A MULTIDISCIPLINARY FIELD TO BE EXPLORED IN BANGLADESH Selina Akter*1, Md. Tanvir Islam 1+2, Mohd Zulkefeli 3, Sirajul Islam Khan 1 1University of Dhaka, Dhaka 1000, Bangladesh 2Jessore Science and Technology University, Jessore 7408, Bangladesh 3 Atta-ur-Rahman Institute for Natural Product Discovery, Universiti Teknologi MARA, Puncak Alam, Selangor, Malaysia Abstract ‘Agarwood’ or ‘eaglewood’ (‘Aguru’ in Bengali) is the most expensive wood in the world, which is an occasional product of a few genera of Aquilaria and Gyrinops in the plant family Thymelaeaceae. Agar is a scented product, oleoresin, obtained from pathological conditions of the wood of live trees containing many aromatic substances. Various bacteria and fungi have been found to be associated with Agarwood formation, although it is still not absolutely clear which are important or even necessary. The quality of agar mostly depends on the plant species and the fungal species involved, as well as, certain other unknown factors. The issues are now to explore the new sources of agarwood to protect the endangered plant species, to ensure agar formation in 100% of the planted trees, upgrade in quality and most possibly quantity of agar yield per tree simultaneously minimizing the maturation time. Both physical and chemical stresses like mechanical wound and induction have long been practiced to enhance agarwood yield as well as fungal inoculation. Specificity of fungal infection is a minor criterion of agarwood formation rather than the plant’s physiological state, immune responses and presence of inducer. The agarwood production could be a multifaceted field of prospects in Bangladesh. The cultivation of new Aquilaria and Gyrinops plants and selection of appropriate inocula and inducers should be the priority objective. A multidisciplinary approach could be initiated with the experts of forestry, mycology, biochemistry and microbiology to achieve the goal. Keyword: aquilaria, agarwood, artificial induction, fungi, perfumery Agarwood ‘Agarwood’ or ‘oodh’ (or just agar) is dark resinous heartwood that forms in Aquilaria and Gyrinops (Blanchette, 2006) trees in the plant family Thymelaeaceae. The heartwood is relatively light and pale coloured; however, as the wood matured (a term used in general sense), the tree produces a dark aromatic resin in response to infection or unknown induction, which results in a very dense, dark, resin embedded heartwood. The resin embedded wood is commonly called gaharu, agarwood, or oud and is valued in many cultures for its distinctive fragrance, and thus is used as incense and perfumes. Agarwood is known under many names in different cultures; In Hindi, it is known as agar, which is originated from Sanskrit aguru. The Sanskrit name aguru is directly used in Bengali (Bouverie, 1885), Telugu and Kannada. It is known as chénxi āng in Chinese, tr ầm h ươ ng in Vietnamese (Th ứ Hai, 2006), and jink ō in Japanese- all meaning "sinking incense". In Japan, there are several grades of jink ō, the highest of which is known as kyara (Kiyoko, 2007). Corresponding Author: *Selina Akter Email: [email protected] Page 22 International Journal of Pharmaceutical and Life Sciences ISSN 2305-0330 Volume 2, Issue 1: January 2013 Both agarwood and its resin distillate/extracts are known as oud in Arabic (Tony, 2005) Western perfumers also use agarwood essential oil under the name "oud" or "oude" (Nathan, 2009). In Europe it was referred to as Lignum aquila (eagle-wood) or Agilawood (Henry and Coke, 1903). Another name is Lignum aloes or Aloeswood (Henry and Coke, 1903). In Tibetan, it is known as a-ga-ru. There are several varieties used in Tibetan medicine: unique eaglewood- ar-ba-zhig; yellow eaglewood- a-ga-ru ser-po, white eaglewood- ar-skya, and black eaglewood- ar-nag (Yuri et al, 1992). In Assamese it is called as "sasi" or "sashi"(panda, 2009). The Indonesian and Malay name is "gaharu"(Henry and Coke, 1903). In Papua New Guinea, it is called "ghara" or eaglewood. In Thai language, it is known as "Mai Kritsana". In Tamil it is called "akil" and in Laos it is known as "Mai Ketsana" (Seng et al., 2005). The tree of concern There are fifteen species in the genus Aquilaria and eight are known to produce agarwood (Ng et al., 1997). In theory agarwood can be produced from all members; however, until recently it was primarily produced from A. malaccensis , A. agallocha and A. secundaria (Broad, 1995). A. crassna and A. sinensis are the other two members of the genus that are usually harvested. At least fifteen species of Aquilaria trees are known to produce the much sought-after Agarwood. In South Asia, Aquilaria achalloga and Aquilaria khasiana are found, particularly in India. Aquilaria malaccensis is mostly known from Malaysia, Indonesia and India, and Aquilaria crassna principally grows in Cambodia, Malaysia, Thailand, and Vietnam. Aquilaria apiculina was found in Philippines, Aquilaria acuminata in Papua New Guinea, Indonesia and Philippines, Aquilaria baillonil in Thailand and Cambodia, Aquilaria baneonsis in Vietnam, Aquilaria beccariana in Indonesia, Aquilaria brachyantha in Malaysia, Aquilaria cumingiana in Indonesia and Malaysia, Aquilaria filaria in New Guinea, the Moluccas, and Mindanao (Philippines) (NPGS/GRIN, 1), Aquilaria grandiflora in China, Aquilaria hirta in Thailand, Indonesia and Malaysia (NPGS/GRIN, 2), Aquilaria microcapa in Indonesia and Malaysia, Aquilaria rostrata in Malaysia, Aquilaria sinensis in China, and Aquilaria subintegra grows in Thailand. Aquilaria sp. is fast-growing, archaic tropical forest tree, which occurs in South and Southeast Asia, from the foothills of the Himalayas to the rainforests of Papua New Guinea. The tree grows in natural forests at an altitude of a few meters above sea level to about 1000 meters, and it grows best around 500 meters in locations with average daily temperatures of 20 to 22ºC (Afifi, 1995; Keller and Sidiyasa, 1994; Wiriadinata, 1995). Aquilaria sp. has adapted to live in various habitats, including those that are rocky, sandy or calcareous, well-drained slopes and ridges and land near swamps. It is a large evergreen tree, growing over 15-40 m tall and 0.6-2.5 m in diameter, and has white flowers (Chakrabarty et al., 1994; Sumadiwangsa, 1997). Trees grow very fast, and start producing flowers and seeds as early as four years old. Agarwood history Formation of agarwood occurs in the trunk and roots of trees that have been infected by parasites. As a response, the tree produces a resin high in volatile organic compounds that aids in suppressing or retarding the infection, a process called tylosis. While the unaffected wood of the tree is relatively light in colour, the resin dramatically increases the mass and density of the affected wood, changing its colour from pale beige to dark brown or black. In natural forest, only about 7% of the trees are infected by fungus. Ascomycetous mold, Phaeoacremonium parasitica (Crous et al., 1996), a dematiaceous (dark-walled) fungus is one of the known fungi reported to be associated with agarwood formation. The odour of Page 23 International Journal of Pharmaceutical and Life Sciences ISSN 2305-0330 Volume 2, Issue 1: January 2013 agarwood is complex and pleasing, with few or no similar natural analogues. As a result, agarwood and its essential oil gained great cultural and religious significance in ancient civilizations around the world, being mentioned throughout one of the world's oldest written texts – the Sanskrit Vedas from India. As early as the third century AD in ancient China, the chronicle ‘Nan zhou yi wu zhi’ (Strange things from the South) written by Wa Zhen of the Eastern Wu Dynasty mentioned agarwood produced in the Rinan commandery, now Central Vietnam, and how people collected it in the mountains. Xuanzang's travelogues and the Harshacharita, written in seventh century AD in Northern India, mentions use of agarwood products such as 'Xasipat' (writing material) and 'aloe-oil' in ancient Assam. The tradition of making writing materials from its bark still exists in Assam. The use of agarwood for perfumery extends back several thousand years, and is referred, for example, in the Old Testament several times using the term ‘aloes’. Agarwood has been used for medicinal purposes for thousands of years, and continues to be used in ayurvedic, Tibetan and traditional East Asian medicine (Chakrabarty et al., 1994; Fratkin, 1994). The Sahih Muslim, which dates back to approximately the eighth century, refers to the use of agarwood for the treatment of pleurisy and its use is referred in the ayurvedic medicinal text the Susruta Samhita. The “Wood of the Gods” has been traded and highly appreciated for thousands of years. The resinous wood or oil extracted is extremely valuable since it is highly regarded for use during Buddhist and Islamic cultural activities, as well as, an important ingredient in many traditional medicines. It is also an extremely important component in traditional Japanese incense ceremonies. Although most people in the United States and Europe are not familiar with this aromatic resinous wood, its use as incense is mentioned several times in the bible. Outside native countries, it is most widely known in the Middle East, China, Taiwan and Japan. A strong connection exists between use, religion and curative properties, and elaborate traditional and religious ceremonies are known from around the world. Faith healers in the Middle East use it at curative ceremonies, Japanese pilgrims donate flowers and agarwood oil to Shinto-Buddhist temples, and Vietnamese religious groups are obliged to bring agarwood to ceremonies at their temples in Mekong delta communities. Agarwood uses Agarwood is extremely highly valued by luxury perfume, fragrance and soap manufacturers. Both agarwood smoke and oil are customarily used as perfume in the Middle East (Chakrabarty et al., 1994).